Implement header navigation component

• Implement non-interactive menu for mobile and large screens
• Implement a minimal interactive menu for large screens
• Implement a minimal, interactive menu for mobile screens
• Update to match current large screen and mobile screen Figma designs (could be a few hours or two days, depending on complexity of CSS)
• Change large screen menu to use hidden instead of opacity to fix subtle issue with hidden menu capturing mouse events
• Change large screen menu to use z-order to ensure dropdown menus always appear above other content

• Implement a simple, interactive menu for large screens

Done in #160

• Implement non-interactive menu for mobile and large screens

This was done in #86

Implement a simple, interactive menu for mobile screens

This step will implement the logic to show and hide the mobile hamburger menu. #172 will implement the content that resides inside of the dropdown menu, once this logic is in place.

Tailwind didn't indicate this clearly, but I needed to make use of both z-order and hidden classes to cause proper showing and hiding.

• Implement a minimal, interactive menu for mobile screens

Completed in #209

• Change large screen menu to use hidden instead of opacity to fix subtle issue with hidden menu capturing mouse events

Done within this PR